Positioning method and apparatus in wireless communication system

Abstract

A method and apparatus for determining a positioning measurement interval in a wireless communication system are disclosed. The method includes acquiring a message including Observed Time Difference of Arrival (OTDOA) related data in a higher layer, wherein the OTDOA related data includes a plurality of cell identifiers and Positioning Reference Signal (PRS) configuration information of corresponding cells, transmitting the ODTOA related data to a physical layer from the higher layer, and determining the RSTD measurement interval by the following Equation by using a plurality of cell-specific PRS periods obtained using the PRS configuration information in the physical layer: T RSTD =T PRS ·(M−1)+Δ where T RSTD denotes the length of the RSTD measurement interval, T PRS denotes the largest of the plurality of cell-specific PRS periods, M denotes the number of PRS positioning occasions, and Δ denotes a measurement time for one PRS positioning occasion.

The invention claimed is:  
     
       1. A method for determining a Reference Signal Time Difference (RSTD) measurement interval at a user equipment in a wireless communication system, comprising:
 acquiring, by the user equipment, a message including Observed Time Difference Of Arrival (OTDOA) assistant data in a higher layer, wherein the OTDOA assistant data includes cell identifiers of a plurality of cells and Positioning Reference Signal (PRS) configuration information of the plurality of cells; 
 delivering, by the user equipment, the OTDOA assistant data to a physical layer from the higher layer; and 
 determining, by the user equipment, the RSTD measurement interval by the following Equation by using a plurality of cell-specific PRS transmission periods obtained using the PRS configuration information:
     T   RSTD   =T   PRS ·( M− 1)+Δ  Equation
 
 
 where T RSTD  denotes the length of the RSTD measurement interval, T PRS  denotes the largest value of the plurality of cell-specific PRS transmission periods, M denotes the number of PRS positioning occasions in the RSTD measurement interval, and Δ denotes a measurement time for one PRS positioning occasion. 
 
     
     
       2. The method of  claim 1 , wherein the RSTD measurement interval starts from a subframe having the nearest PRS positioning occasion after the OTDOA assistant data is transmitted to the physical layer. 
     
     
       3. The method of  claim 1 , further comprising providing, by the user equipment, RSTD measurement information to a location server after the RSTD measurement interval has elapsed. 
     
     
       4. The method of  claim 3 , further comprising providing, by the user equipment, RSTD measurement information about one or more cells satisfying a predetermined condition within the RSTD measurement interval to the location server. 
     
     
       5. The method of  claim 3 , further comprising providing, by the user equipment, RSTD measurement information about a reference cell to the location server after a measurement interval determined using a PRS period of the reference cell has elapsed within the RSTD measurement interval. 
     
     
       6. The method of  claim 1 , wherein the message including the OTDOA assistant data is received from a location server through a serving base station. 
     
     
       7. A user equipment configured to determine a Reference Signal Time Difference (RSTD) measurement interval in a wireless communication system, comprising:
 a Radio Frequency (RF) unit; and 
 a processor; 
 wherein the processor acquires a message including Observed Time Difference of Arrival (OTDOA) assistant data in a higher layer, the OTDOA assistant data includes cell identifiers of a plurality of cells and Positioning Reference Signal (PRS) configuration information of the plurality of cells, and the processor delivers OTDOA assistant data to a physical layer from the higher layer and determines the RSTD measurement interval by the following Equation by using a plurality of cell-specific PRS periods obtained using the PRS configuration information:
     T   RSTD   =T   PRS ·( M− 1)+Δ  Equation
 
 
 where T RSTD  denotes the length of the RSTD measurement interval, T PRS  denotes the largest value of the plurality of cell-specific PRS transmission periods, M denotes the number of PRS positioning occasions in the RSTD measurement interval, and Δ denotes a measurement time for one PRS positioning occasion. 
 
     
     
       8. The user equipment of  claim 7 , wherein the RSTD measurement interval starts from a subframe having the nearest PRS positioning occasion after the OTDOA assistant data is transmitted to the physical layer. 
     
     
       9. The user equipment of  claim 7 , wherein the processor provides RSTD measurement information to a location server after the RSTD measurement interval has elapsed. 
     
     
       10. The user equipment of  claim 9 , wherein the processor provides RSTD measurement information about one or more cells satisfying a predetermined condition within the RSTD measurement interval to the location server. 
     
     
       11. The user equipment of  claim 9 , wherein the processor provides RSTD measurement information about a reference cell to the location server after a measurement interval determined using a PRS period of the reference cell has elapsed within the RSTD measurement interval. 
     
     
       12. The user equipment of  claim 7 , wherein the message including the OTDOA assistant data is received from a location server through a serving base station.